• Journal of Microbiology and Biotechnology
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• v.22 no.5
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• pp.585-591
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• 2012

The antagonistic effect of Trichoderma harzianum on a range of seed-borne fungal pathogens of wheat (viz. Fusarium graminearum, Bipolaris sorokiniana, Aspergillus spp., and Penicillium spp.) was assessed. The potential of T. harzianum as a biocontrol agent was tested in vitro and under field conditions. Coculture of the pathogens and Trichoderma under laboratory conditions clearly showed dominance of T. harzianum. Under natural conditions, biocontrol effects were also obtained against the test fungi. One month after sowing, field emergence (plant stand) was increased by 15.93% over that obtained with the control treatment, and seedling infection was reduced significantly. Leaf blight severity was decreased from 22 to 11 at the heading stage, 35 to 31 at the flowering stage, and 86 to 74 at the grain filling stage. At harvest, the number of tillers per plant was increased by 50%, the yield was increased by 31.58%, and the 1,000-seed weight was increased by 21%.

• Mycobiology
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• v.43 no.3
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• pp.210-217
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• 2015

A seed-borne fungus, Curvularia sp. EML-KWD01, was isolated from an indigenous wheat seed by standard blotter method. This fungus was characterized based on the morphological characteristics and molecular phylogenetic analysis. Phylogenetic status of the fungus was determined using sequences of three loci: rDNA internal transcribed spacer, large ribosomal subunit, and glyceraldehyde 3-phosphate dehydrogenase gene. Multi loci sequencing analysis revealed that this fungus was Curvularia spicifera within Curvularia group 2 of family Pleosporaceae.

• Korean Journal of Agricultural Science
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• v.9 no.1
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• pp.275-283
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• 1982

One hundred and sixteen seed samples of 16 different crops were tested by routine seed health testing methods. Seeds of rice, soybean and barley were found to be associated with 18, 15 and 7 species of fungi, respectively. Discoloration and spotting of various kinds were observed in rice seeds. Epicoccum purpurascens, Pyricularia oryzae and Trichoconiella pedwickii were higher in these discoloured than in normal seeds of rice. Macrophomina phaseolina, the charcoal-rot fungus is a new record for soybean in Korea. Seeds of sesame were infected by 13 fungi Alternaria sesami, A. sesarmicola and Corynespora cassiicola were detected predominantly. Twenty one species of fungi were detected in seed samples of 12 commercial vegetable crops. Alternaria, Colletotrichum and Fusarium were found predominantly. Some seed samples of commercial vegetable crops were heavily infected with pathogenic fungi and showed heavy seed and seedling rot.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2000.10a
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• pp.13.2-13
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• 2000

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.3
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• pp.370-376
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• 2012

Disease is the major problem in ginseng cultivation from seed stratification, soil preparation prior to planting, right through to drying of the roots. There are many soil-borne disease pathogen in rhizosphere soil environment, furthermore occurrence of diseases by a diverse group of fungi and related organisms are closely related to various soil condition. Observable symptoms for soil-borne diseases include wilting, leaf death and leaf fall, death of branches and limbs and in severe cases death of the whole plant. The fungus Cylindrocarpon destructans is the cause of root rot characterized by a decay of the true root system in many ginseng production areas in Korea. Some pathogens are generally confined to the juvenile roots whilst others are capable of attacking older parts of the root system. However, the relation between the soil environmental characteristics and ginseng root rot by soil-borne disease pathogen is not clearly identified in ginseng field. In this paper, we reviewed soil-borne plant pathogen causing root rot disease of ginseng with respect to soil environment.

• Korean Journal of Medicinal Crop Science
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• v.21 no.1
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• pp.27-31
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• 2013

This study was conducted to isolate and identify the fungal pathogen causing seedling rot of Lithospermum erythrorhizon Siebold & Zuccarini, and to know the optimum growing temperature for decreasing seedling rot of Lithospermum erythrorhizon. On the basis of morphological characteristics, EF-1a sequence analysis, and pathogenecity to host plant, the fungi isolated from seedling rot and seeds of Lithospermum erythrorhizon were identified as Fusarium fujikuroi, indicating that disease causing fungus is seed-borne pathogen. Optimum temperature for germination of seeds of Lithospermum erythrorhizon was $15{\sim}20^{\circ}C$, but pathogenicity of Fusarium fujikuroi was shown more readily at $25{\sim}30^{\circ}C$. These results suggested that seedling culture of Lithospermum erythrorhizon between $15^{\circ}C$ and $20^{\circ}C$ might reduce seedling rot of Lithospermum erythrorhizon caused by seed-borne pathogen Fusarium fujikuroi.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.136.1-136
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• 2003

Bacterial grain rot by Burkholderia gluae cause severe damage in seedling and grain of rice after heading season. This seed-borne pathogen play a role as first infection agent that could be cause disease following cropping season. Until now the direct isolation of the bacteria has some trouble by interference of other bacteria existed inside seed. This study established convenient identification method as simple isolation with KB medium from seed showing symptom and using PCR identification. By this isolation method, B. glumae was isolated from 40 to 50％ in brown rice and inner hull, however, there were saprophytic bacteria and fungi outer hull. In PCR identification with Ogf4 and Ogr3 primer to these 25 isolates, the amplified products were presented in all of the collections but not in 10 saprophytic germs. The isolation rate was constant to 3 months stored seeds. This result provide a rapid and convenient isolation and identification of B. glumae.

• Korean Journal of Agricultural Science
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• v.10 no.2
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• pp.263-268
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• 1983

In a survey of seed-borne mycofloras of Glycine max, 21 species have been isolated. Alternaria tenuis, Aspergillus spp., Cercospora kikuchii, Penicillium spp. and Fusarium spp. were the predominant fungi. C. kikuchii was isolated more often from purple stained seed than from unstained seed, and Fusarium spp., Phomopsis sp., Aspergillus spp. and Penicillium spp. were isolated less frequently in stained than unstained seeds. In inoculation experiments, C. kikuchii, Colletotrichum dematitum, Phomopsis sp. produced mild to severe symptoms on leaves when suspension of their conidia and mycelia were sprayed on to plants. In soil inoculation experiments, Fusarium oxysporum, F. moniliforme and F. semitectum showed pathogenicity causing seed rot and seedling blight.

• Korean journal of applied entomology
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• v.18 no.3 s.40
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• pp.119-126
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• 1979

From the sample seeds of rice cultivar Palkoeng with the brown spot symptom, Helminthosporium oryzae was detected in $86\~92\%$ of hulls including empty glumes, lemma, palea, and rachilla in five to seven days of incubation. When the seeds were dehulled, the percentage detection decreased to $74\~83\%$ of pericarps. The fungus sporulated on whole surface of the seed and was detected within about ten cell layers deep of endosperm but not detected in embryo. Fusarium moniliforme was found in embryo as well as pericarp and endosperm. The frequency of F. roseum, Trichoconis padwickii, Curvularia spp., Atternaria tenuis, Cladosporium cladosporoides and Phoma sp. was less than three percent of hulls and pericarps. In seven days of incubation, $60\~87\%$ of the germinating seeds showed the symptom of H. oryzae while $13\~40\%$ were apparently healthy. This fungus in hilum of infected rice transmitted through pericarp to plumule shoot and radicle of the germinating seed.

• Journal of Life Science
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• v.30 no.2
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• pp.178-185
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• 2020

Rice bakanae is a typical seed-borne and seed-transmitted disease caused by infection by Fusarium fujikuroi. Seed disinfection using chemical fungicides (such as benomyl and prochloraz) is most effective in controlling the disease, but the emergence of fungicide-resistant strains has recently been increasing. Slightly acidic hypochlorous acid water (SAHW) is a safe and environmentally friendly disinfectant that has a potent and broad spectrum of antimicrobial activity against viruses, bacteria, and fungi. In this study, we aimed to investigate the effectiveness of SAHW against F. fujikuroi strains, including chemical fungicide-resistant strains, as an alternative to conventional chemical fungicides in the management of bakanae disease. SAHW showed strong but similar levels of antifungal activity among the F. fujikuroi strains with a minimum inhibitory concentration (MIC₉₀) of 5±2.5 ppm of free available chlorine (FAC). In addition, F. fujikuroi cells lost viability completely within 5 min of SAHW treatment due to the lethal damage to cell integrity. When the rice seeds infected by F. fujikuroi were treated with SAHW containing 20±10 ppm of FAC for 12 hr, the efficiencies of seed disinfection and disease control were 95-98% and 90.1-92.6%, respectively. Altogether, our data suggest that SAHW is an effective compound for controlling rice bakanae disease.